1. Field of the Invention
The present invention relates to a ratchet wrench, and more particularly to a ratchet wrench including an improved structure having fewer parts or elements to be easily and quickly assembled and manufactured with a decreased manufacturing cost and having an increased driving torque or strength for preventing the ratchet wrench from being easily and quickly worn out or damaged.
2. Description of the Prior Art
Typical ratchet wrenches comprise a driving head formed or provided on one end portion of a handle and including a chamber or compartment formed in the driving head for pivotally or rotatably receiving or engaging with a driving shank or member or cartridge, and a pawl movably disposed or attached or mounted or secured or engaged in the driving head for selectively engaging with the gear that is formed and provided on the driving shank or member or cartridge and for determining or controlling the rotating or driving direction of the driving shank or member or cartridge with or by the driving head and the handle.
For example, U.S. Pat. No. 6,161,454 to Chaconas, U.S. Pat. No. 6,164,166 to Whiteford, U.S. Pat. No. 6,220,123 to Chen, U.S. Pat. No. 6,260,449 to I-He, U.S. Pat. No. 6,282,991 to Hu, U.S. Pat. No. 6,357,323 to Chi et al., U.S. Pat. No. 6,386,072 to Yuan-Chin et al., U.S. Pat. No. 6,435,062 to McCann, U.S. Pat. No. 6,435,063 to Chen, U.S. Pat. No. 6,467,378 to Chen, U.S. Pat. No. 6,959,626 to Shen, and U.S. Pat. No. 7,114,415 to Chiang disclose several of the typical ratchet wrenches each also comprising a driving head formed or provided on one end portion of a handle and including a chamber or compartment formed in the driving head for pivotally or rotatably receiving or engaging with a driving shank or member or cartridge, and a pawl movably disposed or attached or mounted or secured or engaged in the driving head for selectively engaging with the gear that is formed and provided on the driving shank or member or cartridge and for determining or controlling the rotating or driving direction of the driving shank or member or cartridge with or by the driving head and the handle.
Normally, a controlling or switching device is further required to be provided and engaged into the handle and/or the driving head and coupled or engaged with the pawl for controlling or switching the pawl to engage with the gear at different portions or segments of the gear and thus to determine or control the rotating or driving direction of the driving shank or member or cartridge with or by the driving head and the handle, and thus for allowing various tool shanks, tool extensions, tool elements, fasteners, driven members or the like to be rotated or driven with or by the handle and/or the driving head.
However, the pawl and the controlling or switching device may include a number of parts or elements, and may occupy a great space or volume in the handle and/or the driving head, and the handle and/or the driving head should be drilled or machined or milled with a great space or volume that is large enough to receive and engage with the pawl and the controlling or switching device such that the strength and/or the driving torque of the handle and/or the driving head will be greatly decreased.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional ratchet wrenches or tools or the like.